The present invention relates to the control of electrical devices, and in particular, electric lamps, from remote locations. Even more particularly, the present invention relates to the control of electrical devices such as electric lamps from remote locations through communication links, e.g., radio frequency links. In particular, the present invention relates to a system for controlling electrical devices from remote locations over, for example, radio frequency links and which dispenses with any need to alter the internal wiring of the electrical system, i.e., the internal wiring of a building.
The present invention provides a system for controlling the status of electrical devices, for example, electric lamps, from a remote location via communication links such as radio frequency links, power line carrier links or infrared links. The present invention allows the status of the electrical devices, e.g., on, off and intensity level, to be transmitted back to a master location. The present invention may employ at least one repeater to help ensure reliable communications between the control devices for the electrical devices, for example, specially adapted lighting control devices in accordance with the invention, and at least one master unit. In the preferred embodiment, the master unit generates a radio frequency signal which is transmitted to and received by either or both a control device, such as a light dimmer, and a repeater, which is provided also to relay the control signals to the control device. The repeater is important in the case where the control device is unable to receive the control signals directly from the master unit. The control device then actuates the electrical device to the desired status, returning a radio frequency signal via an antenna to the master unit or to the master unit via the repeater indicating the true status of the electrical device.
In another embodiment, the invention uses power line carrier signals to communicate from master unit to control device and radio frequency signals to communicate from control device to master unit, optionally via a repeater.
In yet another embodiment, the invention uses an RF to power line carrier bridge. RF control signals are transmitted from a master unit to the bridge and converted to PLC signals for receipt by the control devices. The control devices transmit status RF signals to the bridge for conversion to PLC signals for receipt by the master unit.
Although the present invention is directed particularly to a lighting control system, the present invention can be applied to the communication of signals relating to the control and status of other devices, for example, communication equipment, motors, security systems, computers, audio/visual systems, appliances, HVAC (heating, ventilating and air conditioning) systems, etc.
The present invention preferably includes one or more lighting control devices which each include an antenna and a control and communications circuit which activates a controllably conductive device contained within the lighting control device. A controllably conductive device may comprise, e.g. a semiconductor device such as a TRIAC, bipolar transistor, FET, IGBT, etc. or a switch or relay or any other device whose conductive state can be controlled. The lighting control device can also be manually actuable. The lighting control device, according to the preferred embodiment of the invention, includes an RF antenna, a transmitter/receiver and a control circuit for processing signals received from a master unit and for communicating status information to the master unit.
The lighting control device preferably fits into a standard electrical wall box, and the antenna which comprises a part of the control device is sized so as to fit within the standard electrical wallbox or at least within the area defined by the faceplate for the opening of a standard electrical wall box.
According to the invention, the master units can take several forms. In one embodiment, the master unit comprises a table top master which can plug into an electrical outlet, and has a conventional antenna for transmitting and receiving signals. In another form, the master is a wall mount master and is sized such that it fits within the confines of a standard electrical wall box. In either embodiment, the master unit preferably includes a plurality of controls, each associated with a particular electrical control device or a plurality of electrical control devices. As will be explained herein, the association of the electrical control devices to a particular control on the master unit is freely programmable by the user. Further, the master unit may include functions which allow all electrical control devices to be turned on or off simultaneously. In addition, the present invention can include at least one repeater, which helps to ensure that all signals communicated between master and control devices are received by the appropriate receiver, whether the master or the electrical control device. The repeaters employ a repeater sequence for helping to ensure that each receiver receives those signals intended for it.
There are various systems known in the prior art which allow for remote control of electric lamps without hard wiring control lines to the lighting control devices.
In one prior art system, a user can install a so-called three-way electrical switch, i.e., an additional light control switch, into an existing hard wired single control system by replacing an existing manually operated lighting control device with a lighting control device having a radio frequency receiver incorporated therein. The replacement lighting control device is hard wired into the electrical system in the same way as the conventional device to control the lamp in a lighting fixture. The radio frequency receiver is responsive to radio frequency signals generated by a remote battery powered switching device having a transmitter which can be conveniently affixed to a building wall at another location, thereby to provide the three-way switch circuit. The additional battery powered lighting control device has a manually operated lever, which when operated, sends an RF signal to the other electrical control device which is hard wired into the building's electrical system. The hard wired device will then toggle in response from its present state to the opposite state, i.e., from on to off or off to on. Thus, either switching device, the hard wired replacement or the battery powered device, can operate the lamp. Accordingly, a three-way electrical switch can be provided into an existing electrical system without hard wiring the three-way switch into the system. In this prior art system, having the battery powered transmitting switch and the hard wired switch including the receiver, the hard wired receiving switch includes a whip antenna made from a piece of insulated wire which may be allowed to dangle out of the electrical box either outside the building wall or inside the wall. The receiver in the hard wired switch allows only one way communication i.e., it receives signals from the battery powered transmitting switch. Two-way communication between the hard wired switch and the transmitting switch is not provided. A system of this type is sold by Heath Zenith as the Reflex switch. Another device of this type, which instead employs a hand-held remote control to provide a three way switching function, is manufactured by Dimango.
In another prior art system an existing hard wired manually operated lighting control device is replaced with a lighting control device having a radio frequency receiver incorporated therein. The replacement lighting control device is hard wired into the electrical system in the same way as the conventional device to control the lamp in a lighting fixture. The radio frequency receiver is responsive to radio frequency signals generated by a remote battery powered control device having a transmitter which can be conveniently affixed to a building wall at another location. The battery powered control device has switches to enable the selection of four different light levels. The switches when operated cause an RF signal to be sent to the electrical control device which is hard wired into the building's electrical system. The hard wired device responds to the RF signals by adjusting its output to cause the lamp to operate at one of four different predetermined light levels. In addition to responding to RF signals, the hard wired device can also operate in response to the actuation of manually actuated switches incorporated within it. Two way communication between the hard wired device and the battery powered control device is not provided. A system of this type is sold by Leviton as the Anywhere switch.
In another prior art system, known as the X10 system, standard lighting control devices are replaced by lighting control devices operating via a power line carrier (PLC) communication system, i.e., information for operating the lighting control devices is provided over the building existing power line by a power line carrier (PLC). In addition, in some of these systems, an RF communications link is also provided so that a hand held remote control master device can be used to operate the various lighting fixtures. In these systems, an RF repeater may also be provided. In the X10 system, only one way communication is provided so that a master unit is not apprised by a lighting control device of the status of the controlled light fixtures. Also, the user is unable to tell if the command sent by the master was carried out by the lighting control device due to poor communication links caused by noise, burned out light bulbs, etc.
In the X10 system, a radio frequency to PLC bridge is provided to convert radio frequency signals into power line carrier (PLC) communication signals. The RF to PLC bridge plugs into an existing wall outlet and provides the PLC carrier onto the electrical power line to be received by controlled lighting control devices. Typically, the RF to PLC bridge comprises a box which is plugged into an existing wall or electrical outlet and has an antenna for receiving signals from the master controller or a repeater.
In addition to the X10 system, there are also known two-way communications links for providing, in general, home automation. These include the Electronic Industries Association Consumer Electronics Bus (CEBus) (EIAIS-60) protocols for radio frequency media, power line carrier, infrared media and twisted pair media, and the Echelon Corporation LONworks. Intellon Corp. provides transceivers that comply with the CEBus standards for RF and power line carrier. Echelon provides transceivers that comply with their communications protocol. Although these systems in general provide communications links which can be adapted to consumer and home use, none of them provide for the integrated system for controlling electrical devices as described herein.
In addition to the above, a system known as the Smart House supplied by Smart House LP is also available. This system comprises a wired system and, accordingly, would entail expensive alteration and dislocation if applied to the control of electrical devices, particularly lighting in a home.
In addition to the above, the assignee of the present application offers systems known as HomeWorks, NetWorks and LuMaster which are hard-wired control systems controlling lighting devices. Although these systems are suitable for new construction, they entail major alteration and dislocation when applied to existing homes.
Also becoming available are wireless local area networks (LANs) for computer systems, which employ radio frequency communication methods ensuring that all nodes of the network can communicate with each other. See, for example, Electronic Design, Jun. 26, 1995, page 55.